When multiple string wells are installed under water, with the wellhead at or near the bottom of the body of water, it is necessary not only to land devices such as the tubing hanger body by remote operations but also to orient the landed device rotationally with respect to a reference point on the underwater structure. Prior-art workers have devoted much attention to the problems involved in such installations, and the following U.S. Pat. Nos. show typical methods and apparatus which have been proposed: 3,603,401 Nelson et al 3,661,206 Putch et al 3,688,841 Baugh, 3,693,714 Baugh, 3,742,294 Morrill, 3,800,869 Herd et al 3,807,497 Baugh, 3,847,215 Herd.
Despite extensive prior art effort and considerable success in the field, there has been a continuing need for improvement and simplification, particularly with reference to sealing the hanger body after it has been landed and oriented.